наблюдаемость: ввести безопасный контракт метрик

scripts/check-rust-module-boundaries.sh

@@ -47,6 +47,13 @@ check_no_match \
   '^\s*use\s+(axum|sqlx)(::|[;\{])' \
   "$ROOT_DIR/crates/crank-runtime/src"
 
+check_no_match \
+  "product modules must record metrics only through crank-metrics" \
+  '(^|[^[:alnum:]_])(::)?metrics::(counter|gauge|histogram)!' \
+  "$ROOT_DIR/apps" \
+  "$ROOT_DIR/crates" \
+  --glob '!**/crank-metrics/**'
+
 if (( status != 0 )); then
   cat >&2 <<'EOF'
 
@@ -58,6 +65,7 @@ Rules:
 - core remains framework/storage agnostic;
 - registry remains storage-only and HTTP-client agnostic;
 - runtime remains execution-only and storage/framework agnostic.
+- names and labels of metrics remain inside the typed crank-metrics contract.
 
 EOF
 fi